<template>
  <el-container class="home-container">
    <!-- 头部区域 -->
    <el-header>
      <div>
        <img src="../assets/heima.png" alt="主页logo" />
        <span>随心购后台管理系统</span>
      </div>
      <el-button type="info" @click="logout">退出</el-button>
    </el-header>

    <!-- 页面主体区域 -->
    <el-container>
      <!-- 左侧边栏导航 -->
      <el-aside :width="isCollapse ? '64px' : '200px'">
        <!-- 菜单栏折叠与展开 -->
        <div class="toggle-button" @click="toggleCollapse">
          |||
        </div>
        <!-- 侧边栏菜单区域 -->
        <el-menu
          background-color="#333744"
          text-color="#fff"
          active-text-color="#409EFF" 
          unique-opened
          :collapse="isCollapse"
          :collapse-transition="false"
          router
          :default-active="activePath"
        >
          <!-- 一级菜单 -->
          <el-submenu :index="item.id + ''" v-for="item in menulist" :key="item.id" >
            <!-- 一级菜单的模板区域 -->
            <template slot="title">
              <!-- 图标 -->
              <i :class="iconsObj[item.id]"></i>
              <!-- 文本 -->
              <span>{{item.authName}}</span>
            </template>

            <!-- 二级菜单 -->
            <el-menu-item :index="'/' + subItem.path" v-for="subItem in item.children" :key="subItem.id" @click="saveNavState('/' + subItem.path)">
              <!-- 二级菜单的模板区域 -->
              <template slot="title">
                <!-- 图标 -->
                <i class="el-icon-menu"></i>
                <!-- 文本 -->
                <span>{{subItem.authName}}</span>
              </template>
            </el-menu-item>
          </el-submenu>
        </el-menu>
      </el-aside>
      
      <!-- 右侧主体部分 -->
      <el-main>
        <!-- 路由占位符 -->
        <router-view></router-view>
      </el-main>
    </el-container>
  </el-container>
</template>

<script>
export default {
   data() {
    return {
      // 左侧菜单数据
      menulist: [],
      // 左侧菜单icon数据
      iconsObj: {
        '125': 'iconfont icon-user',
        '103': 'iconfont icon-tijikongjian',
        '101': 'iconfont icon-shangpin',
        '102': 'iconfont icon-danju',
        '145': 'iconfont icon-baobiao'  
      },
      // 定义菜单折叠开关
      isCollapse: false,
      // 被激活的菜单导航地址
      activePath: ''
    }
  },
  created() {
    this.getMenuList()
    this.activePath = window.sessionStorage.getItem('activePath')
  },
  methods: {
    // 点击退出按钮
    logout() {
      // 清空token值
      window.sessionStorage.clear()
      // 跳转至登录页面
      this.$router.push('/login') 
    },
    // 点击按钮切换菜单的折叠与展开
    toggleCollapse() {
      this.isCollapse = !this.isCollapse
    },
    // 获取所有的菜单
    async getMenuList() {
      const { data: res } = await this.$http.get('menus')
      // console.log(res)
      if (res.meta.status !== 200) return this.$message.error(res.meta.msg)
      this.menulist = res.data
    },
    // 菜单导航激活状态的高亮显示
    saveNavState(activePath) {
      window.sessionStorage.setItem('activePath',activePath)
      this.activePath = activePath
    }
  },
}
</script>

<style lang="less" scoped>
.home-container {
  height: 100%;
}
.el-header {
  background-color: #373d41;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-left: 0;
  color: #fff;
  font-size: 20px;
  div {
    display: flex;
    align-items: center;
    span {
      padding-left: 15px;
    }
  }
}
.el-aside {
  background-color: #333744;
  .toggle-button {
    background-color: #4A5064;
    color: #fff;
    font-size: 10px;
    line-height: 24px;
    text-align: center;
    letter-spacing: 0.2em;
    cursor: pointer;
  }
  .el-menu {
    border-right: none;
  }
}
.el-main {
  background-color: #eaedf1;
}

.iconfont {
  margin-right: 10px;
}
</style>            